1. Technical Field
The present disclosure relates to universal serial bus (USB) connectors. More particularly, the present disclosure relates to USB connectors of Type C.
2. Description of Related Art
In our daily lives, electrical connectors of universal serial bus (USB) specifications are one of the most widely used transmission interfaces. Since the USB interface is convenient and easy to use, small in size and has a reasonable cost, the applications of USB can be found in various working fields. No matter for the core entertainment devices of a family such as televisions, personal notebook computers, smartphones or tablet devices, computers or printers in an office, or multimedia entertainment systems in a vehicle, USB devices are often used for the task of information transmission.
Apart from the convenient, quick and reliable transmission of information, USB further has another very convenient function: the electricity transmission through the mutual connection between the interfaces of the multimedia electronic devices. This is also referred to as charging. However, the charging of the existing USB devices can only provide a maximum of 7.5 W of power. Although this improvement of specification of power supply can comply with the charging requirements of hand-held portable devices such as mobile phones or music media player of MP3, this is a generally time-consuming method to charge a USB device. In addition, this is inadequate to satisfy with the power supply of large and power consuming products such as screen monitors or notebook computers.
In order to popularize the application of USB on the power supply of various devices, provide multimedia electronic devices which is easy to carry and slimmer, and reduce the situation of transmission failure caused by the wrong direction of insertion or connection of the USB, a brand new universal serial bus of Type C appears accordingly. The USB Implementers Forum (USB-IF) has announced recently the standard specification of this USB interface of Type C. The power supply requirements of various devices can be fulfilled by utilizing a single USB cable with a power transmission as high as 100 W. This can shorten the charging time for the devices, and also optimize the convenience of the mobile application.
Moreover, the interface of USB of Type C can support the brand new slim design of various devices including mobile phones, tablet computers, combo products, notebook computers, desktop computers and devices of many other specific purposes. This slim interface of new standard of the industry can transmit information, power and video, and will become the only interface required by the combination of transmissions of various devices. Since the synchronization of information transmission has been largely increasing, corresponding electromagnetic radiations may be produced during use, interfering the normal operation of other electronic elements. Therefore, the method of grounding is commonly used by the industry to reduce the production of electromagnetic interference (EMI).
As shown in FIGS. 14-15, the Taiwan patent M367498 provides an electrical connector A100. The electric connector A100 includes an insulating casing A1, a metal casing A2 covering the insulating casing A1 and a plurality of conductive terminals A3. The insulating casing A1 includes a rear wall A12 which stands upright, and two side walls A13 extended forwards as a unity from the two ends of the rear wall A12. Moreover, the insulating casing A1 is disposed with a tongue sheet A11. The tongue sheet A11 is substantially extended forwards as a unity from the front of the rear wall A12. The inner walls of the two side walls A13 are disposed with a plurality of openings facing the groove (not shown in the Figs.) of the tongue sheet A11, forming the first, second and third wall surface A131, A132 and A133 in a shape of steps, in which the first wall surface A131 is closest to the bottom wall (not shown in the Figs.) The second wall surface A132 is located between the first wall surface A131 and the third wall surface A133.
The metal casing A2 is formed from a metal sheet, surrounding the side wall A13, top wall (not shown in the Figs.) and bottom wall (not shown in the Figs.) of the insulating casing A1. The top wall (not shown in the Figs.) of the metal casing A2 forms a docking chamber (not shown in the Figs.) with the side wall A13 and the rear wall A12 of the insulating casing A1. The tongue sheet A11 extends into the docking chamber (not shown in the Figs.) from a first direction. The top wall (not shown in the Figs.) and the bottom wall (not shown in the Figs.) of the metal casing A2 are respectively disposed with elastic arms A22 extending towards the docking chamber (not shown in the Figs.), in order to achieve the holding and grounding function to the plug connector (not shown in the Figs.). The front edge of the top wall (not shown in the Figs.) and the bottom wall (not shown in the Figs.) bend outwards, and are punched with a touching sheet A23. The touching sheet A23 can be used for the touching of chassis (not shown in the Figs.) like computers. The two sides of the metal casing A2 extend downwards to form the pins A24. On the other hand, a grounding plate A7 is located between the first surface A110 and the second surface (not shown in the Figs.) of the tongue sheet A11. The dimension of the grounding plate A7 is substantially the same as the area of the tongue sheet A11. The two sides (not shown in the Figs.) of the grounding plate A7 substantially align with the two side surfaces A112 of the tongue sheet A11, without protruding the two side surfaces A112 of the tongue sheet A11. The front end slightly contracts inwards relative to the front end surface A113. The rear end of the grounding plate A7 is disposed with a welding leg A71 as a unity. The welding leg A71 is connected to the grounding circuit of the circuit board (not shown in the Figs.)